The laws behind this have existed since earlier than 1948 [0]. The revision of the form is interesting but censoring anti-government material at ports of entry

The laws behind this have existed since earlier than 1948 [0]. The revision of the form is interesting but censoring anti-government material at ports of entry is far from new. [0] See http://uscode.house.gov/download/XHTML/uscprelim/PRELIMusc18.htm http://uscode.house.gov/download/XHTML/uscprelim/PRELIMusc18... §552. Officers aiding importation of obscene or treasonous books and articles